Recently, the technique of providing a TFT on an inexpensive glass substrate is being rapidly developed. This is because the demand of an AMLCD is increased.
In an AMLCD, each of several tens to several millions of pixels arranged in a matrix form is equipped with a thin film transistor (TFT) as a switching element, and input/output of an electric charge on each of pixel electrodes is controlled by the switching function of the TFT.
A liquid crystal is sandwiched between the pixel electrode and a counter electrode to form a kind of capacitor. Therefore, the electro-optical characteristics of the liquid crystal can be changed by controlling input/output of an electric charge on the capacitor, and thus an image can be displayed by controlling light passing through the liquid crystal panel.
As a characteristic phenomenon in such a display device using a liquid crystal, there is a phenomenon called disclination. While the liquid crystal sandwiched between the pixel electrode and the counter electrode is arranged with orientation having regularity, the orientation may be disturbed by rubbing failure due to unevenness on the surface of the electrodes. The function of light shutter is lost in the location at which disclination occurs, and display failure such as leakage of light arises.
In order to prevent disclination, measures have been conducted such as covering the TFT with a flattened film, but such cannot become drastic countermeasures because flattening of the contact part of the pixel electrode finally produced is impossible even if a flattened film is utilized.
The invention has been developed in view of the above-described problems.